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TY - CONF AU - Shibata, T. AU - Fan, K. AU - Ishii, K. AU - Matsumoto, H. AU - Sugimoto, T. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - The New High Field Septum Magnets for Upgrading of Fast Extraction in Main Ring of J-PARC J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - The J-PARC Main Ring (MR) is working on imporved beam to 750 kW by shorting the repetition period from 2.48 s to 1.3 s which we call 1Hz operation. There are fout high field septum magnet along the fast extraction line in the MR, and these will be improved to the new magnets which can operate 1Hz frequency. The new high field septa will be installed in 2021. In this poster we will report about the performance of these new septum magnets. These high field septum magnets are called Septum 30(SM30), 31(SM31), 32(SM32), 33(SM33). We will replace SM30, SM31, and SM32. One reasons of cethe replacement is installation of a large-size quadrupole magnet to upsteam postion of the septa. We need to change the longitudinal length of the septa. Second is large aperture of the beam duct for reduction of beam loss by the collision of the halo of the proton beam to the duct. The new high field SM30, SM31 and SM32 have large aperture. and the material of the beam ducts for extraction line are ceramics for reduction of amount of heat generation by eddy current on the surface of the duct. The maetial of the circulating duct are titanium for reduction of radioactivation. On the other hand, the power supply will not be replaced, then the current power supplies will be used for these new septa. The new SM30, SM31, and SM32 were produced in 2015. The first test operation of SM31 were conduced with 2.48 s repein 2015, and we have meaured the magnetic field without problem. In 2018, we conduced the first 1Hz operation with SM30. The minimum repetition period of the operation was 1.16 s without any problem. We measuered magnetic fields in the gap of the pole and in the circulating beam duct. In this report we will report the detail of the results of the operation and field measurement. PB - JACoW Publishing CP - Geneva, Switzerland SP - 2001 EP - 2004 KW - operation KW - extraction KW - septum KW - flattop KW - power-supply DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-TUPTS030 UR - http://jacow.org/ipac2019/papers/tupts030.pdf ER -